Dinosaurs lived millions of years ago before mankind existed. The word means, “terrible lizard.” Knowledge about dinosaurs comes from fossils of their footprints and bones. Most of them had fat bodies, thin necks and small heads. Some had wings and could fly. Some had spikes on their backs and tails. Dinosaurs came in all sizes and most of them were found on land. Some of the dinosaurs were Tyrannosaurus Rex, the water-inhabiting Brachiosaurus, and the Pteranadon which had wings spanning 25 feet.